NORTHRIDGE, California — They were at the parting of the Red Sea and the Battle of Gettysburg. They were there when Peter Parker first revealed his powers, and when Luke Skywalker destroyed the Death Star. They are extras, the background performers who fill up the screen to add authenticity and life where it might otherwise be lacking, and there is nobility in their unsung existence. And so for one glorious day, I joined their illustrious ranks to become a small part of Hollywood history.

"We're just sheep, and now's the part of the day they take us out of the pen," she said, turning mournfully to look up. "They tell us where to go, what to do and now where to graze." The girl I knew only as Ryan and I were standing in the lunch line on the set of the new film "Super Bad," and super bad was how most of us felt. We were tired and hungry and being corralled across the street and under a tent. She was an extra, not that she or anybody I met would call it that. "We're background players or background actors," Hillary from Toluca Lake, California, told me, joking that her biggest role to date was as a corpse on "CSI: NY" before adding, "We do more than just lie around."

5:50 a.m.: My alarm was set for 5:30, but I don't wake up until 10 minutes to six — plenty of time, I reassure myself, to get dressed and drive to the set for an 8 a.m. call.

6:45 a.m.: I finish getting dressed, finally settling on a T-shirt, jeans and jacket combo. The film's publicist asked that I dress like I'm from New Jersey. Since I was born there, grew up there and spent four years of college there, this request completely baffles me. Seriously. You try it. Dress North Dakotan.

7:30 a.m.: On the road to the set I get the first of two frantic calls from the publicist asking me where I am. Apparently, the call time was changed from 8 to 7:30, and that makes me late. Even though this isn't my fault in any conceivable way, it marks the first of what would be several times throughout the day that I should have been fired.

8:01 a.m.: I pull up to set parking and meet Kym Langlie, my on-set contact. She gives me the once over before admonishing, "You might look too good." Judging from the flannels and ripped jeans of the other extras I see, I gather that by "New Jersey" she meant "Seattle." Fifteen years ago.

8:03 a.m.: Kym tells me about the scenes being shot today, which revolve around Seth (Jonah Hill) discovering someone at a party deposited bodily fluids on his pants. Don't even ask what those bodily fluids are. Honestly, that's all I have to say about that. P-E-R-I-O-D.

8:04 a.m.: Actually, Kym explains, what the movie is really about is two best friends from high school who are going off to different colleges. "It's the Jungian separation thing," she says. I see.

8:15 a.m.: I listen to a speech from Nikki, the second, second assistant director. This, I learn, is her actual unironic title.

8:18 a.m.: Nikki picks five or so extras for the first scene, which takes place in a small kitchen. "I always wonder why when they pick certain people," a male extra to my right remarks. "Maybe I'm ugly."

8:30 a.m.: Outside the set, I get paired up with Molly, a petite brunette I'm told to flirt with during the scene. I do not need to be told this twice. Molly fondly remembers her best extra gig, "Red Eye." She reminds me it was mostly shot in one location. "That's 28 straight days on a plane," she says. "It's the Holy Grail of extra work."

8:40 a.m.: Still waiting to get called onto the set, Molly reveals to me her real job is as a personal assistant to her "wealthy sister ... a famous author of best-selling books." Since I had just heard someone say they fought in the Queen's Navy last summer, I have my doubts. "No, no," she argues, "It's true. I was the inspiration for the Cameron Diaz character in 'In Her Shoes.' "

8:42 a.m.: He did fight in the Queen's Navy, as an extra on "Pirates of the Caribbean." I can't believe I now have to trust everything I hear.

8:45 - 9 a.m.: We walk onto the set. The scene we're shooting now is a quick one: Seth opens the fridge at a party to grab a beer and is pushed out of the way by Mark (Keith Loneker). Keith is a former professional football player roughly twice my size.

9:02 a.m.: "What am I doing back here in the corner of the kitchen? I need business," Keith says. He turns to me and proclaims, "You, you're my business!"

9:04 a.m.: I regain control of my bowels.

9:05 a.m.: Keith and I discuss the scene we're about to perform. It's going to start out with the two of us looking at each other, pretending to talk. Then he's going to see Seth out of the corner of his eye, pat me on the back and head over to push him. "Stand in my way. The more I have to move you, the more I look like an asshole," he says. "It's more real that way."

9:06 - 9:10 a.m.: We rehearse the scene and then shoot it multiple times. The first time, I was nervous. The second, I was excited. By the 13th time, I was exhausted and bored.

10:10 a.m.: My scene is done and in the can. It'll be roughly seven seconds long in the movie — that is, if it actually makes it into the movie. We spent over an hour on it. How in the world do films get made?

10:20 - 10:40 a.m.: Even though I'm not in the next scene, which takes place in the living room at the same party, I stand to the side and watch. There must be 45 extras here, filling up the background. I have no idea how anyone can possibly keep track of it all, but every take, each extra does exactly the same thing he or she did the take before. These people are pros.

10:45 a.m.: I overhear director Greg Mottola talking to a writer about how to make the scene funnier. Perhaps they could make the offending word a past tense? Maybe the person "made" the bodily fluid on Seth's pants?

10:50 - 11:10 a.m.: Jonah, Greg and several others go out back, where they try to find ways of making the scene funnier by ad libbing and throwing ideas back and forth. This is by far my favorite part of the day, watching the creative team come up with on-the-spot improvements for the script. Sure, the scene is crude, but it's also funny. I must have seen it 50 times by the end of their impromptu powwow, and I still chuckle each time.

11:30 a.m. - 2 p.m.: For most of the next two hours I wander around talking to various extras in the tent, or inside the house.

Right before a 2 p.m. lunch, I wander over to take a seat in the extras' pen. A friendly looking blond-haired man saddles up beside me. "I realized two months ago that I don't want to act anymore, which is what I came out here for," he revealed. "What happened was that I found God." I can't tell if he's talking about his faith or working on "The Passion of the Christ." I've been an extra too long already.